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result(s) for
"Hamada, S"
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Association between mobility patterns and COVID-19 transmission in the USA: a mathematical modelling study
by
Du, Hongru
,
Badr, Hamada S
,
Marshall, Maximilian
in
Analysis
,
Betacoronavirus
,
Coronavirus Infections - epidemiology
2020
Within 4 months of COVID-19 first being reported in the USA, it spread to every state and to more than 90% of all counties. During this period, the US COVID-19 response was highly decentralised, with stay-at-home directives issued by state and local officials, subject to varying levels of enforcement. The absence of a centralised policy and timeline combined with the complex dynamics of human mobility and the variable intensity of local outbreaks makes assessing the effect of large-scale social distancing on COVID-19 transmission in the USA a challenge.
We used daily mobility data derived from aggregated and anonymised cell (mobile) phone data, provided by Teralytics (Zürich, Switzerland) from Jan 1 to April 20, 2020, to capture real-time trends in movement patterns for each US county, and used these data to generate a social distancing metric. We used epidemiological data to compute the COVID-19 growth rate ratio for a given county on a given day. Using these metrics, we evaluated how social distancing, measured by the relative change in mobility, affected the rate of new infections in the 25 counties in the USA with the highest number of confirmed cases on April 16, 2020, by fitting a statistical model for each county.
Our analysis revealed that mobility patterns are strongly correlated with decreased COVID-19 case growth rates for the most affected counties in the USA, with Pearson correlation coefficients above 0·7 for 20 of the 25 counties evaluated. Additionally, the effect of changes in mobility patterns, which dropped by 35–63% relative to the normal conditions, on COVID-19 transmission are not likely to be perceptible for 9–12 days, and potentially up to 3 weeks, which is consistent with the incubation time of severe acute respiratory syndrome coronavirus 2 plus additional time for reporting. We also show evidence that behavioural changes were already underway in many US counties days to weeks before state-level or local-level stay-at-home policies were implemented, implying that individuals anticipated public health directives where social distancing was adopted, despite a mixed political message.
This study strongly supports a role of social distancing as an effective way to mitigate COVID-19 transmission in the USA. Until a COVID-19 vaccine is widely available, social distancing will remain one of the primary measures to combat disease spread, and these findings should serve to support more timely policy making around social distancing in the USA in the future.
None.
Journal Article
Computational Insights on the Potential of Some NSAIDs for Treating COVID-19: Priority Set and Lead Optimization
by
Abo Elmaaty, Ayman
,
B. Elkaeed, Eslam
,
Al-Karmalawy, Ahmed A.
in
Anti-Inflammatory Agents, Non-Steroidal - chemistry
,
Anti-Inflammatory Agents, Non-Steroidal - metabolism
,
Anti-Inflammatory Agents, Non-Steroidal - therapeutic use
2021
The discovery of drugs capable of inhibiting SARS-CoV-2 is a priority for human beings due to the severity of the global health pandemic caused by COVID-19. To this end, repurposing of FDA-approved drugs such as NSAIDs against COVID-19 can provide therapeutic alternatives that could be utilized as an effective safe treatment for COVID-19. The anti-inflammatory activity of NSAIDs is also advantageous in the treatment of COVID-19, as it was found that SARS-CoV-2 is responsible for provoking inflammatory cytokine storms resulting in lung damage. In this study, 40 FDA-approved NSAIDs were evaluated through molecular docking against the main protease of SARS-CoV-2. Among the tested compounds, sulfinpyrazone 2, indomethacin 3, and auranofin 4 were proposed as potential antagonists of COVID-19 main protease. Molecular dynamics simulations were also carried out for the most promising members of the screened NSAID candidates (2, 3, and 4) to unravel the dynamic properties of NSAIDs at the target receptor. The conducted quantum mechanical study revealed that the hybrid functional B3PW91 provides a good description of the spatial parameters of auranofin 4. Interestingly, a promising structure–activity relationship (SAR) was concluded from our study that could help in the future design of potential SARS-CoV-2 main protease inhibitors with expected anti-inflammatory effects as well. NSAIDs may be used by medicinal chemists as lead compounds for the development of potent SARS-CoV-2 (Mpro) inhibitors. In addition, some NSAIDs can be selectively designated for treatment of inflammation resulting from COVID-19.
Journal Article
Introducing the antibacterial and photocatalytic degradation potentials of biosynthesized chitosan, chitosan–ZnO, and chitosan–ZnO/PVP nanoparticles
2024
The development of nanomaterials has been speedily established in recent years, yet nanoparticles synthesized by traditional methods suffer unacceptable toxicity and the sustainability of the procedure for synthesizing such nanoparticles is inadequate. Consequently, green biosynthesis, which employs biopolymers, is gaining attraction as an environmentally sound alternative to less sustainable approaches. Chitosan-encapsulated nanoparticles exhibit exceptional antibacterial properties, offering a wide range of uses. Chitosan, obtained from shrimp shells, aided in the environmentally friendly synthesis of high-purity zinc oxide nanoparticles (ZnO NPs) with desirable features such as the extraction yield (41%), the deacetylation (88%), and the crystallinity index (74.54%). The particle size of ZnO NPs was 12 nm, while that of chitosan–ZnO NPs was 21 nm, and the bandgap energies of these nanomaterials were 3.98 and 3.48, respectively. The strong antibacterial action was demonstrated by ZnO NPs, chitosan–ZnO NPs, and chitosan–ZnO/PVP, particularly against Gram-positive bacteria, making them appropriate for therapeutic use. The photocatalytic degradation abilities were also assessed for all nanoparticles. At a concentration of 6 × 10
–5
M, chitosan removed 90.5% of the methylene blue (MB) dye, ZnO NPs removed 97.4%, chitosan-coated ZnO NPs removed 99.6%, while chitosan–ZnO/PVP removed 100%. In the case of toluidine blue (TB), at a concentration of 4 × 10
–3
M, the respective efficiencies were 96.8%, 96.8%, 99.5%, and 100%, respectively. Evaluation of radical scavenger activity revealed increased scavenging of ABTS and DPPH radicals by chitosan–ZnO/PVP compared to individual zinc oxide or chitosan–ZnO, where the IC50 results were 0.059, 0.092, 0.079 mg/mL, respectively, in the ABTS test, and 0.095, 0.083, 0.061, and 0.064 mg/mL in the DPPH test, respectively. Moreover, in silico toxicity studies were conducted to predict the organ-specific toxicity through ProTox II software. The obtained results suggest the probable safety and the absence of organ-specific toxicity with all the tested samples.
Journal Article
Limitations of using mobile phone data to model COVID-19 transmission in the USA
2021
Mobile phone data provide a unique means to capture individual-level and population-level movement patterns, which have become heavily relied upon to inform COVID-19 responses—specifically, for evaluating the impact of, and compliance with, non-pharmaceutical interventions (NPIs), as well as modelling the spatiotemporal variability of transmission dynamics. Furthermore, we applied the analysis to subgroups of counties clustered spatially and temporally according to both the magnitude of their outbreaks and growth (or decline) rates during specified periods, in efforts to distinguish the role of mobility patterns in SARS-CoV-2 transmission as a function of these characteristic outbreak dynamics. While mobility patterns can serve as a critical tool for assessing COVID-19 intervention impacts, there exists various challenges and limitations to their use.4 Based on our most recent findings, parameterising SARS-CoV-2 transmission models using mobility data alone is likely to result in poorly performing models and inaccurate forecasts.
Journal Article
Structure elucidation and evaluation of the antimicrobial and antitumor activities of 5-methylthiazole-based Schiff base and its metal chelates
2026
The current thiazole Schiff base ligand was obtained upon reacting 2-amino-5-methylthiazole with 2,4-dihydroxybenzaldehyde (
H
2
L
). The transition metal chelates then were presented by reacting the ligand with Mn(II), Cu(II), and Zr(IV) salts in 1:1 molar ratio forming chelates,
1
,
2
and
3
, respectively. The reaction of the ligand with Cd(CH₃COO)₂ afforded Cd(II) complex,
4
, in the molar ratio 2L:1 M. The type of contact that occurs between metal ions and the thiazole ligand was investigated by the assistance of magnetic susceptibility, FTIR, mass, UV–Visible and
1
H NMR spectral and micro-elemental analyses. The resulting data demonstrated that the ligand–metal interaction happened via the phenolic O-atom
ortho
-position and the imine group N- atom which is dehydrogenated to form the metal complexes. Solvent molecules attached to the metal ions in complexes, whether present or absent were suggested using TGA in addition to thermodynamic activation parameters for the thermal decomposition steps were computed by the Eyring equation. Magnetic moment and UV–Visible measurements indicated formation of square planar Cu(II) chelate and octahedral Zr(IV) chelate, while the Mn(II) and Cd(II) ions formed tetrahedral metal chelates. XRD and TEM used to reveal structural microcrystalline data of both the organic compound (
H
2
L
) and inspected complexes. The patterns of X‐ray diffraction introduced the crystalline nature of each of the free ligand, complexes
1
,
3
and
4
, whereas complex
3
was relatively amorphous without an even dispersion of the solid constituents throughout the precipitation procedure. The study rigorously analyzed molecular structures using Density Functional Theory (DFT) calculations, revealing significant variations in ligand bond lengths and angles upon complexation, and demonstrating the electron-donating and accepting properties of HOMO and LUMO orbitals. Biological activity for the prepared compounds was accomplished. They exhibited high activity, especially after chelation. The Antimicrobial activity afforded very auspicious data upon comparison with the applied reference antibiotic. The greatest anti-cancer activity has been achieved by Cu(II)-complex
2
which showed IC
50
value = 16.89 µg/ml against MCF-7 cell lines which is greater than the IC
50
value of scaled drug applied (IC
50
of 5-flurouracil = 28.0 µg/ml). Promising bioactive compounds’ binding affinities with HepG-2 and MCF-7 DNA helices were estimated to apply molecular docking.
Journal Article
Impact of platelet transfusion on outcomes in trauma patients
by
Boutonnet, M.
,
Vigué, B.
,
Duranteau, J.
in
Blood Coagulation Disorders - etiology
,
Blood platelets
,
Care and treatment
2022
Background
Trauma-induced coagulopathy includes thrombocytopenia and platelet dysfunction that impact patient outcome. Nevertheless, the role of platelet transfusion remains poorly defined. The aim of the study was 1/ to evaluate the impact of early platelet transfusion on 24-h all-cause mortality and 2/ to describe platelet count at admission (PCA) and its relationship with trauma severity and outcome.
Methods
Observational study carried out on a multicentre prospective trauma registry. All adult trauma patients directly admitted in participating trauma centres between May 2011 and June 2019 were included. Severe haemorrhage was defined as ≥ 4 red blood cell units within 6 h and/or death from exsanguination. The impact of PCA and early platelet transfusion (i.e. within the first 6 h) on 24-h all-cause mortality was assessed using uni- and multivariate logistic regression.
Results
Among the 19,596 included patients, PCA (229 G/L [189,271]) was associated with coagulopathy, traumatic burden, shock and bleeding severity. In a logistic regression model, 24-h all-cause mortality increased by 37% for every 50 G/L decrease in platelet count (OR 0.63 95% CI 0.57–0.70;
p
< 0.001). Regarding patients with severe hemorrhage, platelets were transfused early for 36% of patients. Early platelet transfusion was associated with a decrease in 24-h all-cause mortality (versus no or late platelets): OR 0.52 (95% CI 0.34–0.79;
p
< 0.05).
Conclusions
PCA, although mainly in normal range, was associated with trauma severity and coagulopathy and was predictive of bleeding intensity and outcome. Early platelet transfusion within 6 h was associated with a decrease in mortality in patients with severe hemorrhage. Future studies are needed to determine which doses of platelet transfusion will improve outcomes after major trauma.
Journal Article
Innovative PBAT/PU/MMT@ZnO-NPs bionanocomposite films based on modified montmorillonite for active food packaging
2026
Egypt’s plastic garbage problem is becoming worse. The fabrication of biodegradable polymers is an inventive way to decline this pollution. The objective of the current work was to prepare the active packaging bionanocomposites films based on biodegradable poly(butylene adipate-co-terephthalate (PBAT), Polyurethane (PU) and organically modified layered silicates montmorillonite (MMT) containing Zinc oxide nanoparticles (ZnO-NPs) by different concentration (2.5%, 5%, 10%) to improve mechanical and antimicrobial properties of the created bionanocomposite films. Furthermore, the manufactured Poly(butylene adipate-co-terephthalate(,Polyurethane, Montmorillonite, ZnO nanoparticles (PBAT/PU/MMT@ZnO-NPs) bionanocomposite films were assessed using FT-IR, TGA, XRD, SEM, TEM and mechanical properties. Moreover, the barrier properties including water vapor transmission rate (WVTR) in addition the oxygen transmission rate (OTR) of the achieved (PBAT/PU/MMT@ZnO-NPs) bionanocomposite films were evaluated. The fabricated bionanocomposite films demonstrated proper thermal stability. The results showed that adding modified MMT incorporating ZnO-NPs to the PBAT/PU matrix improved the mechanical characteristics, biodegradation, and antibacterial activity. For potential uses in food packaging, the current study provides extremely exciting opportunities for sustainable PBAT/PU-based renewable and antibacterial films.
Journal Article
Robust antiviral activity of commonly prescribed antidepressants against emerging coronaviruses: in vitro and in silico drug repurposing studies
2022
During the current coronavirus disease 2019 (COVID-19) pandemic, symptoms of depression are commonly documented among both symptomatic and asymptomatic quarantined COVID-19 patients. Despite that many of the FDA-approved drugs have been showed anti-SARS-CoV-2 activity in vitro and remarkable efficacy against COVID-19 in clinical trials, no pharmaceutical products have yet been declared to be fully effective for treating COVID-19. Antidepressants comprise five major drug classes for the treatment of depression, neuralgia, migraine prophylaxis, and eating disorders which are frequently reported symptoms in COVID-19 patients. Herein, the efficacy of eight frequently prescribed FDA-approved antidepressants on the inhibition of both SARS-CoV-2 and MERS-CoV was assessed. Additionally, the in vitro anti-SARS-CoV-2 and anti-MERS-CoV activities were evaluated. Furthermore, molecular docking studies have been performed for these drugs against the spike (S) and main protease (M
pro
) pockets of both SARS-CoV-2 and MERS-CoV. Results showed that Amitriptyline, Imipramine, Paroxetine, and Sertraline had potential anti-viral activities. Our findings suggested that the aforementioned drugs deserve more in vitro and in vivo studies targeting COVID-19 especially for those patients suffering from depression.
Journal Article
Phenylpyrazolone-1,2,3-triazole Hybrids as Potent Antiviral Agents with Promising SARS-CoV-2 Main Protease Inhibition Potential
by
Musa, Arafa
,
Abdelgawad, Mohamed A.
,
Aljuhani, Ateyatallah
in
1,2,3-triazole
,
Amino acids
,
antiviral activity
2023
COVID-19 infection is now considered one of the leading causes of human death. As an attempt towards the discovery of novel medications for the COVID-19 pandemic, nineteen novel compounds containing 1,2,3-triazole side chains linked to phenylpyrazolone scaffold and terminal lipophilic aryl parts with prominent substituent functionalities were designed and synthesized via a click reaction based on our previous work. The novel compounds were assessed using an in vitro effect on the growth of SARS-CoV-2 virus-infested Vero cells with different compound concentrations: 1 and 10 μM. The data revealed that most of these derivatives showed potent cellular anti-COVID-19 activity and inhibited viral replication by more than 50% with no or weak cytotoxic effect on harboring cells. In addition, in vitro assay employing the SARS-CoV-2-Main protease inhibition assay was done to test the inhibitors’ ability to block the common primary protease of the SARS-CoV-2 virus as a mode of action. The obtained results show that the one non-linker analog 6h and two amide-based linkers 6i and 6q were the most active compounds with IC50 values of 5.08, 3.16, and 7.55 μM, respectively, against the viral protease in comparison to data of the selective antiviral agent GC-376. Molecular modeling studies were done for compound placement within the binding pocket of protease which reveal conserved residues hydrogen bonding and non-hydrogen interactions of 6i analog fragments: triazole scaffold, aryl part, and linker. Moreover, the stability of compounds and their interactions with the target pocket were also studied and analyzed by molecular dynamic simulations. The physicochemical and toxicity profiles were predicted, and the results show that compounds behave as an antiviral activity with low or no cellular or organ toxicity. All research results point to the potential usage of new chemotype potent derivatives as promising leads to be explored in vivo that might open the door to rational drug development of SARS-CoV-2 Main protease potent medicines.
Journal Article
Flash drought onset over the contiguous United States: sensitivity of inventories and trends to quantitative definitions
by
Christian, Jordan I.
,
Zaitchik, Benjamin F.
,
Otkin, Jason A.
in
Air temperature
,
Arid regions
,
Arid zones
2021
The term “flash drought” is frequently invoked to describe droughts that develop rapidly over a relatively short timescale. Despite extensive and growing research on flash drought processes, predictability, and trends, there is still no standard quantitative definition that encompasses all flash drought characteristics and pathways. Instead, diverse definitions have been proposed, supporting wide-ranging studies of flash drought but creating the potential for confusion as to what the term means and how to characterize it. Use of different definitions might also lead to different conclusions regarding flash drought frequency, predictability, and trends under climate change. In this study, we compared five previously published definitions, a newly proposed definition, and an operational satellite-based drought monitoring product to clarify conceptual differences and to investigate the sensitivity of flash drought inventories and trends to the choice of definition. Our analyses indicate that the newly introduced Soil Moisture Volatility Index definition effectively captures flash drought onset in both humid and semi-arid regions. Analyses also showed that estimates of flash drought frequency, spatial distribution, and seasonality vary across the contiguous United States depending upon which definition is used. Definitions differ in their representation of some of the largest and most widely studied flash droughts of recent years. Trend analysis indicates that definitions that include air temperature show significant increases in flash droughts over the past 40 years, but few trends are evident for definitions based on other surface conditions or fluxes. These results indicate that “flash drought” is a composite term that includes several types of events and that clarity in definition is critical when monitoring, forecasting, or projecting the drought phenomenon.
Journal Article